A double-focusing electrostatic electron spectrometer has been used to measure the K—LL Auger spectra resulting from electron impact for each of the elements in the gaseous molecules N2, O2, CO, NO, H2O, and CO2. An energy resolution of 0.09% full width half-maximum was normally employed. A method for analyzing these complex spectra is described. It involves the identification of normal and satellite lines. The former are defined as arising from single electron ionization from the K shell without additional excitation followed by an Auger process in which one electron fills the vacancy while a second goes into the continuum, and where all the other electrons remain in their same orbitals. Satellite lines result when extra excitation occurs either in the initial formation of the K vacancy or in the subsequent Auger process. To aid in the identification of these satellite lines, auxiliary experiments have been performed such as the study of discrete energy losses in photoionization due to electron shake-up, and the comparison of Auger spectra produced by monoenergetic x rays. As a consequence of the analyses of the Auger spectra, information has been obtained on (1) the nature of initial excitation processes such as the transition of a K electron into excited discrete states and monopole excitation and (2) the identification of the energy and nature of the ground and excited states of the doubly charged molecular ions. The second ionization potential was obtained for each of the molecules, and in one case, N2, the third ionization potential was estimated. Finally, a brief discussion is made of the possible use of high resolution electron spectroscopy in molecular as well as elemental analysis.

An electron spectrometer which employs double focusing electrostatic plates is described. The photoelectron spectra obtained by bombarding methane, silane, germane, methyl fluoride, difluoromethane, and trifluoromethane with 21.22-eV photons are presented. The experimental ionization energies are compared with theoretical and other experimental data, and molecular-orbital assignments are made for the energy values obtained. Broad double maximum bands were observed in the case of methane, silane, and germane and are discussed in terms of Jahn–Teller distortion for the positive ions. Possible correlation of the methane spectrum with interstellar space data is also discussed.

Angle-resolved photoelectron spectroscopy was carried out on the first nine valence orbitals of benzene using synchrotron radiation as a photon source. From these data cross sections σ and angular distribution parameters β were obtained over a photon energy of 10 to 34 eV. The experimental results are compared with calculations for the same parameters, based on the multiple scattering Xα method. Considering the complexity of the molecule, the comparison is gratifying. A number of shape resonances, which are predicted, have been identified experimentally. The orbital assignments for the photoelectron spectrum of benzene have been reexamined in view of the cross sections and angular distributions and have for the most part been verified.

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The angular distribution parameter, /?, has been measured for the resonant Auger spectra in Kr following 3d--Sp excitation. Unusually low values, close to -1, were seen for two bands. From optical spectroscopy data these bands are assigned to the final states 4p 4 ( 3 P)5p( 4 Ps/2, V3/2, and 4 D^/i). According to angular-momentum transfer theory, some of the transitions could be parity unfavored, yielding p values of -1, but additional theory is required for complete understanding. Implications for angular studies of highly resolved Auger spectra are discussed.